Overview
- Published in Scientific Reports on January 22, the University of Manchester–led analysis with Bristol and Melbourne researchers reassesses locomotion in extinct macropods.
- The team measured hindlimbs from 94 modern and 40 fossil specimens spanning 63 kangaroo and wallaby species, including giant lineages such as Protemnodon.
- Calculations show fourth metatarsals were strong enough to resist hopping stresses and heel bones (calcanei) were broad enough to anchor the tendon widths required.
- The authors conclude hopping was feasible but likely intermittent because thicker tendons would store less elastic energy, making long-distance hopping inefficient.
- The findings overturn earlier scaling-based limits that deemed hopping impossible above roughly 150–160 kilograms (about 330–350 pounds) and suggest brief hopping could aid predator evasion; the largest known species, Procoptodon goliah, stood about 2 meters tall.